The present invention relates to a device for monitoring usage of audiovisual equipment. In particular, the present invention relates to automating the process of positioning a magnetic pick-up device that monitors radiation emitted from a television set. The magnetic pick-up device is used as part of a television audience monitoring system to determine a channel to which a television set, set-top converter box or video cassette recorder is tuned.
Determining a number of viewers watching a particular television program is of great importance to television networks, stations, programmers and advertisers. Information regarding the number of viewers is used to determine market share and the ratings of particular programs. This information is additionally used to determine advertising rates, which in turn affects the revenue generated by the television networks and stations.
There are numerous systems known in the art that attempt to monitor the viewing habit of television watchers. Early attempts at monitoring were fairly simple and unsophisticated, and generally required viewers to maintain a diary of programs watched. As the viewers began and finished watching a particular channel or program, they entered a start and end time in to the diary. The viewers periodically mailed the diaries to a central collection location, which then processed the diaries. The disadvantages of such a system are many, including: failure to enter information into the diaries, inaccurate entries into the diaries, and delays in processing. Further, as the number of channels provided to households has increased dramatically, it has become increasingly difficult for viewers to accurately track their viewing habits.
Later attempts have become more sophisticated and efficient by automating portions of the data collection process and the determination of the channel currently being viewed. For example, U.S. Pat. No. 4,642,685, to Roberts et al., discloses a television monitoring system having a channel detection unit, a people monitoring unit, a transmission unit, and a receiving unit. The channel detection unit detects ultra or very high frequency radiation emitted from a television tuner to determine if the channel being tuned is one of the channels which have been preset into the detection unit. The detection is performed by a pick-up probe that inductively couples the signal emitted from the local oscillator of the television receiver. The people monitor unit is a powered handset that includes buttons assigned to each of the individuals who will be viewing the television set. The viewer depresses his or her assigned button to indicate he or she has started to watch the television. The viewing data is stored and transmitted by the transmission unit over household wiring to the receiving unit. The receiving unit sends the collected information to a central computer via a telephone connection. While this system speeds the data transmission process to the central computer as compared to mailing diaries to a processing center, there are several disadvantages in this system. For example, those of skill in the art will recognize that the location of the pick-up probe will greatly affect the sensitivity and accuracy of the channel detection unit. Further, as each viewer must manually depress a button on the people monitor, it is subject to the same inaccuracies of the diary method noted above, i.e., the failure of viewers to record the television channels actually watched.
U.S. Pat. No. 4,907,079, to Tuner et al., describes networked conventional audio and visual equipment that communicate via telephone lines with a remote central computer. The viewer provides channel selection commands or other programming commands to a microprocessor through an infrared remote control. A VCR tuner and TV tuner within the system provide audio and video signals for the conventional television monitor or television receiver. An AM and FM radio tuner may also be included, tunable by the microprocessor. In the Tuner et al. system, the video and/or audio signals from each tuner, video tape player, and disc players are coupled to the input side of an audio switch and a video switch. The switches are microprocessor controlled so that the audio and video program from any source may be coupled to any output or display device at the viewing location. The system includes a motion detector to determine the presence of viewers and provides for communication with a remote computer to monitor use of each networked audiovisual unit. While this system provides for monitoring and logging of each networked audiovisual unit, the Tuner et al. system is designed to control a large home-entertainment system, rather than a small-scale solution to monitoring viewers"" habits. In particular, the Turner et al. system is indicated to cost a few hundred dollars, and would fail to provide a solution to television networks and advertisers who are interested in obtaining accurate viewing statistics by deploying systems to a relatively large number of viewers.
U.S. Pat. No. 4,912,552, to Allison, III, et al., describes a system that collects television channel tuning data that transmits the data to a central site in a transparent manner to the occupants of the household. The system is designed having a hub and spoke architecture, where the hub unit communicates with metering devices attached to television receivers and/or cable television converters. The meters are periodically polled by the hub, which then collects the data acquired by each meter. The hub communicates with a host computer via standard telephone lines. The Allison, III, et al. system particularly describes the central hub device and gathering data before transmitting it to the central site. However, the Allison, III et al. system fails to provide an improved metering unit by contemplating the use of known channel meters.
U.S. Pat. No. 5,374,951, to Welsh, discloses a system for monitoring and recording data related to television program viewing habits that includes a plurality of remote program monitor units that automatically report such data to a central computer via a conventional telephone network. The monitor unit reads a character string that is decoded from the demodulated television signal received by the unit. The character string is compared to a string table stored within the unit to determine the content being viewed by the television watcher. If there is a match, an event code and a time are stored in the unit for reporting to the central computer. However, for the system to operate, the character string must be encoded into the received television signal, otherwise there will be no match with the string table stored in memory. Further, the string table must be kept current for the system to provide accurate results.
U.S. Pat. No. 5,382,970, to Kiefl, describes a system for monitoring and collecting data on the viewing habits of television viewers that includes a portable personal data collection device that is separate from the television or set-top converter. The personal data collection devices includes a detector for providing a station identifier identifying the particular broadcast signal being received by the receiver, a clock for providing a signal representing time, a memory for storing data, and a cellular telephone module for communicating with a central location. The cellular telephone module periodically transmits stored data within the device to the central location. The viewer may enter channel information directly into the device, or the device may include a detector for detecting a channel selection signal from a television remote control to change the station identifier stored in memory. While this is an improvement over diaries, this system requires a personal data collection device for each individual watching a particular television set. Further, because the device is physically separate from the television set, the data collected may not be accurate as viewers may either fail to enter channel information or the device may not detect an infrared transmission from the television remote control.
U.S. Pat. No. 5,495,282, to Mostafa, et al., discloses a tuning/monitoring module for monitoring use of a video equipment without the use of probes by injecting RF signals into a cable converter and a VCR in order to detect channels selected by the cable converter and the VCR. In accordance with signals received from the cable converter and the VCR, the tuning/monitoring module can determine a selected channel being viewed by the viewers. Channel identification signals are also injected into the VCR and cable converter for recording by the VCR on videotape. The state of the xe2x80x9cTV/VCRxe2x80x9d switch of the VCR is determined by injecting a code signal into the VCR and determining whether that signal is present in an RF video signal output by the VCR. The receiver also receives data contained in channel identification signals. The receiver is selectively connectable to the VCR and the cable converter. However, this system requires the use of the special tuning/monitoring module in place of a tuner provided with a television or VCR in order to provided the injected signal to determine the viewed channel. Such a special tuning/monitoring module increases the expense associated with tracking viewers"" habits.
In view of the above, there is a need for an integrated solution to detect the channels being watched by viewers. There is also a need for a system that does not interfere with any of the consumer""s electronics, equipment or features. In particular, there is a need for a system that provides channel information without requiring addition steps to be taken by viewers, and that functions such that the consumer""s VCR, TV, remote controls are not tampered with or opened and continue to operate normally.
In view of the above, the present invention, through one or more of its various aspects and/or embodiments is thus presented to accomplish one or more objects and advantages, such as those noted below.
In accordance with an aspect of the present invention, there is provided a signal strength metering device for use in positioning a magnetic pick-up device that receives signals radiated from a television set. The signal strength metering device comprises a synchronizing signal processing section that includes a first filter, a first peak amplitude detection circuit, a first edge detection circuit, and a one-shot circuit, where the synchronizing signal processing section receives a vertical synchronizing signal, and the one-shot outputs a blanking signal upon receipt of a first voltage signal from the first edge detection circuit. The first voltage signal is representative of a peak amplitude of the vertical synchronization signal. The signal strength metering device also includes a first audio signal processing circuit that has a second filter, a second peak amplitude detection circuit and a second edge detection circuit. The first audio signal processing circuit receives an audio signal from the television set and the blanking signal, and outputs a second voltage representative of a peak amplitude of the audio signal and a first square wave representation of the audio signal. The signal strength metering device further includes a second audio signal processing circuit that has a blanking circuit and a third edge detector. The second audio signal processing circuit receives a test audio signal and outputs a second square wave representative of the test audio signal. The signal strength metering device additionally includes a controller that receives the second voltage signal representative of the peak amplitude of the audio signal, the first square wave and the second square wave. The controller determines at least one of a quality of the vertical synchronizing signal, a level of the audio signal, a phase of the audio signal, and an audio noise floor measurement.
In accordance with a feature of the invention, the synchronizing signal processing circuit comprises a peak compare circuit having at least one comparator. The peak compare circuit determines if a leading edge of the vertical synchronizing signal is a positive edge having a greater amplitude or if the leading edge is a negative edge having a greater amplitude. In addition, the peak compare circuit may include a dual color LED, wherein if the leading edge of the vertical synchronizing signal is positive and greater in amplitude, the dual color LED is illuminated a first color to indicate the vertical synchronizing signal is in-phase, and wherein if the leading edge is negative and greater in amplitude, the dual color LED is illuminated a second color to indicate the vertical synchronizing signal is out-of-phase.
In accordance with another feature, the first filter comprises a low pass filter and a band pass filter, wherein the band pass filter is tuned to cause the vertical synchronizing signal to ring.
In accordance with a further feature, the first audio signal processing circuit further includes a DC buffering amplifier, wherein the DC buffering amplifier presents a second voltage representative of the peak amplitude of the audio signal to the controller. The second voltage may be sampled by the controller to determine the voltage representative of the peak amplitude of the audio signal. Also, the second voltage may be presented across a capacitor, such that the controller may discharge the capacitor and determine a length of time for the capacitor to recharge to a logic high value to determine the voltage representative of a peak amplitude of the audio signal.
In accordance with yet another feature, the second audio signal processing circuit further comprises a phase inverter, wherein the controller compares a phase of the first square wave output to a phase of the second square wave, and if the first square wave and the second square wave are out-of-phase, then the phase inverter inverts the test audio signal such that it is in-phase with respect to the audio signal.
In accordance with another feature of the invention, the signal strength metering device further comprises an LED display that indicates at least one of the quality of the vertical synchronizing signal, the level of the audio signal, the phase of the audio signal, and the audio noise floor measurement.
The controller may determine the quality of the vertical synchronizing signal,by sampling the blanking signal a predetermined number of times, taking an average of the samples, and comparing the average to an average of a previously determined predetermined number of samples, wherein if a difference between the two averages is less than a first predetermined amount a preferred LED of the LED display is illuminated, wherein if the difference is greater than a second predetermined amount a fail LED of the LED display is illuminated, and wherein if the difference of the two averages falls between the first and second predetermined amounts, a pass LED of the LED display is illuminated.
The level of the audio signal may be determined by sampling the audio signal a predetermined number of times and determining an average of the samples, and wherein an audio indicator LED of the LED display is illuminated to reflect the level of the audio signal.
The phase of the audio signal may be determined by comparing a timing between leading edges of the audio signal and the test audio signal, wherein if the leading edges of the audio signal and the test audio signal are within a predetermined timing window of each other, they are determined to be in-phase and a first LED of the LED display is illuminated, wherein if the leading edge of one signal is within the predetermined timing window of the falling edge of the other signal, they are determined to be in inverted phase and a second LED of the LED display is illuminated, and wherein if the signal edges of the audio signal and the test audio signal fall outside of the predetermined timing window, they are determined to be out-of-phase and a third LED of the LED display is illuminated.
The audio noise floor measurement may be determined by blanking the test audio signal, and an ambient noise level is determined by the microcontroller and displayed by a noise level indicator LED of the LED display.
In accordance with a further feature of the present invention, the signal strength meter is electrically coupled to the magnetic pick-up device and the magnetic pick-up device detects at least one of the synchronization signal and the audio signal, and wherein the magnetic pick-up device provides at least one of the synchronization signal and the audio signal to the signal strength meter. The magnetic pick-up device may be further connected to a viewership meter that has an audio matching circuit that compares a local audio signal of a predetermined channel tuned by the viewership collection meter with the audio signal output by the television to which a set-top converter is connected. If the local audio signal and the audio signal match, the viewership collection meter determines that the channel to which the set-top converter box is tuned is the predetermined channel.
In accordance with a further aspect of the present invention, there is provided a signal strength metering device, comprising first means for processing a synchronizing signal, the first processing means receiving the synchronizing signal and outputting a blanking signal representative of a positive peak value of the synchronizing signal; second means for processing a television audio signal and a test audio signal, the second means receiving the television audio signal and the test signal and outputting a voltage representative of an amplitude of the television audio signal, a first square wave representative of the television audio signal, and a second square wave representative of the test signal; means for controlling the signal strength metering device, the controlling means receiving the blanking signal, the first square wave and the second square wave and determining a quality of the first signal, a level of the second signal, and a phase of the second signal; and means for displaying at least one of the quality of the synchronizing signal, the level of the television audio signal, and the phase of the television audio signal.
According to a feature of the present invention, the controlling means determines the quality of the synchronizing signal by sampling the blanking signal a predetermined number of times, taking an average of the samples, and comparing the average to an average of a previously determined predetermined number of samples, and wherein the controlling means instructs the displaying means to display a result of the comparison of the averages.
According to another feature, the level of the television audio signal is determined by sampling the television audio signal a predetermined number of times and determining an average of the samples, and wherein the controlling means instructs the displaying means to display a result of the comparison of the averages.
According to a further feature, the phase of the television audio signal is determined by comparing a timing between leading edges of the television audio signal and the test audio signal, wherein results of the comparison is displayed by the displaying means.
According to yet another feature, the signal strength meter is electrically coupled to a magnetic pick-up device and the magnetic pick-up device detects at least one of the synchronization signal and the television audio signal, and wherein the magnetic pick-up device provides at least one of the synchronization signal and the television audio signal to the signal strength meter. The magnetic pick-up device may be further connected to a viewership meter that has an audio matching circuit that compares a local audio signal of a predetermined channel tuned by the viewership collection meter with the audio signal output by the television to which a set-top converter is connected. If the local audio signal and the audio signal match, the viewership collection meter determines that the channel to which the set-top converter box is tuned is the predetermined channel.
In accordance with yet another aspect of the present invention, there is provided a signal strength metering device which receives signals from an electronic device. The device comprises a first signal processing circuit that has a first filter, a first peak amplitude detection circuit, a first edge detection circuit and a one-shot circuit. The first signal processing circuit receives a synchronizing signal and outputs a second voltage representative of a peak amplitude of the first signal and a first square wave representation of the first signal. The device also includes a second signal processing circuit that has a second filter, a second peak amplitude detection circuit and a second edge detection circuit. The second signal processing circuit receives an audio signal and the synchronizing signal, and outputs a voltage representative of a peak amplitude of the second signal and a first square wave representation of the second signal, The signal strength meter further includes a third signal processing circuit that has a blanking circuit, a phase inverter and a third edge detector. The third signal processing circuit receives a third signal and outputs a second square wave representative of the third signal. In addition the metering device includes a controller that receives the voltage representative of the peak amplitude of the second signal, the first square wave and the second square wave, and a display comprising a plurality of LEDs. The controller determines at least one of a quality of the first signal, a level of the second signal, and a phase of the second signal, and the display indicates results of the determination of at least one of the quality of the first signal, the level of the second signal, and the phase of the second signal.
Other features of the invention are described below.